Korea reunions
People who were originally from North Korea or have their family members in North Korea, bow in the direction of the North during a memorial service for their family members near the demilitarized zone separating the two Koreas, in Paju, 55 km (34 miles) north of Seoul on January 31, 2014, Reuters/Kim Hong-Ji

South Korea has rejected the North's demand that it postpone by a few days joint military drills with the U.S. scheduled for this month, an official said Thursday according to a Reuters report, which added that the North may again cancel a reunion of families separated by the Korean War, like it did in September.

"North Korea persistently demanded the postponement of the joint exercise for two days where it overlaps the reunions. As far as we're concerned, it's impossible," South Korea's Unification Minister Ryoo Kihl-jae reportedly told the parliament.

The demand was made at a high-level meeting between the two Koreas on Wednesday in Panmunjom village. North Korea expressed concerns that these joint drills are a rehearsal for the U.S. to launch a war. Both countries were supposed to hold a reunion of the separated families at Mount Kumgang and, last week, the North had threatened to cancel these reunions if the drills continued.

"It does not make sense to carry out the reunion of families, who were separated due to the War, during a dangerous nuclear war practice," a spokesman for the North Korean Policy Department of the National Defense Commission said last week, according to CNN.

The reclusive North also cancelled an invitation to Robert King, a U.S. human rights envoy to visit the country to discuss the release of Kenneth Bae, an American imprisoned by Pyongyang. Secretary of State John Kerry, who is scheduled to begin a tour to Asia Wednesday, is expected to bring up the subject of North Korea and its nuclear ambitions with South Korean and Chinese officials during his trip.

"North Korea in the first place has no willingness to hold reunions and it looks likely to fall apart," Lee Ji-sue a professor at Myongji University in Seoul told Reuters. "Even if it goes ahead, the reunions will end up being an one-off event."